1. Field of the Invention
The present invention is related to a reworking method for removing defects on integrated circuit devices, and particularly, to a reworking method for removing defects on the conductive layer of a metal interconnection and for rebuilding the conductive layer to reduce the scrape rate of the integrated circuit device.
2. Description of the Prior Art
Integrated circuit devices have a tendency toward higher density and higher integration. In recent years, integrated circuit devices are formed as multi-layered metal interconnections for increasing the electrical connections between the metal interconnections themselves or between the integrated circuit devices and the metal interconnections. The fabrication process of the integrated circuit devices is very complicated. Integrated circuit devices are typically fabricated after gone through hundreds of different processing steps. For example, during the process of the formation of the metal interconnection, a barrier layer, a metal layer, and an anti-reflective layer are sequentially formed on a wafer having a dielectric layer thereon; then, the definition of the pattern is performed by lithographic and etching processes.
However, particle contamination occurs during many of the processing steps, and thereby results in yield loss. These particles can be disposed onto the surface of the respective integrated circuit devices, and resulting in bridging or broken circuit connections between two components, and causing damage to normal functions. Besides, when the compositions of the deposited film are irregular, the integrated circuit may end up having a rugged surface, with defects such as a hillock or a void formed on the surface. These defects can result in signal timing discrepancies and undesirable parametric yield loss, thus affecting the quality of the integrated circuit devices thereby failing quality inspection, and is to be assessed as defective products, and thus cannot be transferred to the next production step. Moreover, sometimes entire batch of wafers having defects must be scraped. As a result, scraping of wafers not only increases product cost, reduces utilization efficiency of equipments, and delays delivery of the products.